Position selecting device

ABSTRACT

Position selecting device for transferring number or character values stored in an electronic calculating unit to mechanical calculating and printing units, and for setting said number values. The selecting device comprises a power source, a pulse transmitter and also for each number position a setting mechanism. The device may be used in connection with, for instance, cash registers.

United States Patent [191 Englund [451 Dec. 31, 1974 POSITION SELECTINGDEVICE [75] Inventor: John Sven Englund, Ektorp, Sweden [73] Assignee:I-lugin Kassaregister AB, Stockholm,

Sweden [22] Filed: Oct. 10, 1972 [21] App]. No.: 296,231

[30] Foreign Application Priority Data Oct. 8, 1971 Sweden 12770/71 [52]U.S. Cl. 235/156, 235/61 PG, 235/61 PJ [5]] Int. Cl G06c 9/00 [58] Fieldof Search 235/156, 61 PG, 61 PH,

235/61 PJ, 61 PK; 101/93 R, 93 C [56] References Cited UNITED STATESPATENTS 3,009,635 11/1961 Deighton 235/61 PG 3,063,625 11/1962 Bodnar etal. 235/61 PG 3,146,941 9/1964 Heise 235/61 PH 3,652,826 3/1972 Chekroun235/61 PG 3,691,360 12/1972 Gross et a1 235/61 PK PrimaryExaminer-Charles E. Atkinson Attorney, Agent, or Firm-Cushman, Darby andCushman [57] ABSTRACT Position selecting device for transferring numberor character values stored in an electronic calculating unit tomechanical calculating and printing units, and for setting said numbervalues. The selecting device comprises a power source, a pulsetransmitter and also for each number position a setting mechanism. Thedevice may be used in connection with, for instance, cash registers.

12 Claims, 10 Drawing Figures PATENTEI] DEBS 1 I974 SHEET 10F 2 PNENTEDDEC 3 T 4 SHEET 2 0F 2 POSITION SELECTING DEVICE The invention relatesto a position selecting means or device for transferring characters ornumber values stored in an electronic calculator to mechanicalcalculating or printing mechanisms. The position selecting meansconnects an electronic calculating unit to a mechanical or calculatingor printing mechanism and comprises a power source and a pulsetransmitter, and also for each type position a setting mechanism.

Transfer of characters or number values, either from a keyboard of acalculator, cash register or the like, or from an electronic calculatorto a mechanical calculating or printing mechanism has previously beenaccomplished with a variety of types of equipment. In calculators ithas, for instance, been common to use guide rules, often spring biased,operated via a keyboard. These guide rules often transfer, via acomplicated mechanism of levers and toothed segments, a linear guiderule movement into a rotational movement in an indicating unit or aprinting unit. In such cases there is initially a positive couplingbetween guide rule and indicating wheel, disengagement between saidparts taking place when the desired relative position has been arrivedat. Thereafter said movement is completed. For resetting it is requiredthat the direction of movement is reversed. I

The object of the invention is to provide a simple and reliable positionselecting means which eliminates the drawbacks of previous types ofposition selecting means, especially the drawbacks of reciprocatingguide rails. Another object is to provide a position selecting meanshaving a reliable resetting function. Still another object is to make itpossible to perform printing against still-standing printing blocks,thus requiring that the indicating units are at a standstill for a whilebefore resetting occurs. It is also required that the position selectingmeans be simple and inexpensive to manufacture.

This is accomplished, according to the present invention, by providing aposition selecting means having the features indicated in the appendingclaims.

The invention will now be described, by way of exam ple, with referenceto the accompanying drawings, in which FIG. 1 shows schematically acomplete registrating unit of which the position selecting means is apart,

FIG. 2 is a perspective view of a portion of the position selectingmeans showing-only essential parts,

FIG. 3 is a schematical elevation of some of the parts shown in FIG. 2,said parts being positioned in a starting position for setting,

FIG. 4 is similar to FIG. 3 but shows the parts in position at the verybeginning of a setting operation,

FIG. 5 is similar to FIG. 3 but shows the parts after a completedsetting operation,

FIGS. 6-8 correspond to FIGS. 3 5 showing another embodiment,

FIG. 9 is an elevation of a setting unit, and

FIG. 10 is a section along the line X-X in FIG. 9.

The registration equipment shown in FIG. 1 comprises an electroniccalculating unit 1, a control unit 2 having a keyboard and also aposition selecting unit 3 having a mechanical printing unit 4 attachedthereto.

These different parts, which are connected to each other, can bepositioned in different ways relative to each other, and can forinstance be integrated into a single unit. The position selecting means3 and the printing unit can be mounted separately from the calculatingunit 1 and the operating unit 2, which in turn can be combined or bemounted separately. The registration equipment is preferablyelectrically operated.

The operating unit 2 is operated manually and is used to introducecertain data into the calculating unit and to process them therein. Asdesired some of these data, or some calculation results based on thesedata, can then be transferred to the position selecting means 3, whichtransfers the electrical signals introduced into the calculating unitinto corresponding movement of mechanical parts so that the printingunit 4 will produce a receipt 5 or similar printed matter with theinformation wanted.

Of the various units in the registration equipment only the positionselecting means 3 will be described in more detail in the following. Forthe sake of clarity FIG. 2 shows only the parts essential forunderstanding of the invention, and only two out of several mutuallyidentical character or number positions in the position selecting means3 are shown. A power source in the form of an electrical motor 6 iscontrolled by the calculating unit 1 and drives via gear wheels 8, 9 and10 which are mounted on the end plate 7, a setting shaft 11 which hasone end journalled in the end plate 7. On the setting shaft 11 ismounted a setting unit 12 comprising a blocking wheel 13 and a gearwheel 14. Said blocking wheel and gear wheel are connected to each otherby means of an intermediate part 15 acting as a clutch and permitting alimited relative movement. The setting unit 12 can by means of theclutch be made to rotate together with the setting shaft 11. The gearwheel 14 is in engagement with an intermediate wheel 17 rotatablymounted on a shaft 16, said intermediate wheel being in engagement withan indicating wheel 19 rotatably mounted on a shaft 18, said indicatingwheel indicating in a window on the position selecting means the numberthat has been set. The gear wheel 17 is also in engagement with asetting wheel 20 that via a shaft 21 is connected to the printing unit4. The shafts l6 and 18 have one end supported in the end plate 7. Theshaft 21 comprises a number of nested tubular shafts for axially spacedgear wheels. The innermost tubular shaft is journalled in the end plate7. The gear wheel 9 also en gages the gear wheel 22 which is rotatablysupported by the end plate 7 and is fixedly attached to a cam disc 23which in turn via a shaft 24 is fixedly attached to a pulse generatingdisc 25 that is provided with a number of indicating holes 26. As thepulse generating disc rotates, the indicating holes 26 will pass anindicator unit 27 that extends on both sides of the pulse generatingdisc and is connected to the calculating unit 1.

The cam disc 23 operates a cam follower 28 that is attached to an arm 29pivotably supported by the end plate 7. In the free end 30 of the arm 29is provided a bar 31 which is parallel to the setting shaft 11 and bymeans of the arm 29 is movable in a direction perpendicular to itslengthwise direction. On a blocking shaft 32, which is parallel to thebar 31 and has one end mounted in the end plate 7, is arranged a platelike upper blocking device 33 which is movable in a plane perpendicularto the lengthwise direction of the blocking shaft. The upper blockingdevice 33 is arranged to be operated by the bar 31 and also by a lowerblocking device 34 movable mainly in the same plane as the upperblocking device. The lower blocking device is mounted on a shaft 35secured to the end plate 7 and parallel to the blocking shaft 32. Arelay 36 controlled by the calculating unit 1 operates the lowerblocking device 34, which in turn via a spring 37 operates the upperblocking device 33. The upper blocking device 33 and the lower blockingdevice 34 are arranged to be in mutual engagement in various positions.In some of its positions the upper blocking device can be in engagementwith notches 39 on the circumference of the blocking wheel 13 by meansof a blocking stud 38.

FIGS. 3-5 show schematically the different parts essential for thesetting sequence in various positions during a setting sequence. As isevident from these figures the blocking wheel 13' is along itscircumference provided with 10 evenly spaced notches 39 andcorresponding blocking teeth 40 of which nine have the same length andone tooth 41 is longer than the others. The upper blocking device 33,which is rotatable on the blocking shaft 32, can have three differentpositions. In the uppermost of these positions the blocking stud 38engages one of the notches 39. In the intermediate po sition the shortblocking teeth 40, but not the longer blocking tooth 41, can pass theblocking stud 38. In the lowermost position also the long blocking tooth41 can pass the blocking stud 38. The upper blocking device 33 isprovided with a hole 42 through which the bar 31 extends. Further, onits lower side it is provided with an upper abutment or shoulder 43 anda lower abutment 44, said abutments cooperating with a locking member 45on the lower blocking device 34. The lower blocking device 34 can havetwo different positions, an upper position in which the relay 36 is notengaged, and a lower position in which the relay 36 is engaged.

The cam disc 23 which via the cam follower 28, the arm 29 and the bar 31operates the upper blocking device 33, has its periphery divided intothree different cam surfaces, e.g. an outer cam surface 46, anintermediate cam surface 47 and an inner cam surface 48 and intermediatetransition surfaces. The cam disc 23 is, as is the case also for thepulse generating disc 25, common for all number positions. However,there can be more cam discs and/or pulse generating discs. The gearratio between the cam disc 23 and the setting shaft 11, via the gearwheels 9, l0 and 22, is such that the setting shaft 11 rotates onerevolution while the cam follower 38 slides along the inner cam surface48. This means that the cam disc 23 rotates slower than the settingshaft 11. In the embodiment shown the pulse generating disc 25 isprovided with nine indicating holes 26 corresponding to the characters1-9, said indicating holes being arranged on a circular arc. Seen fromthe shaft 24 the juxtapositioned indicating holes 26 are located betweentwo radii defining a center angle which is substantially equal to thecentre angle between the radii at the ends of the cam surface 48.

The indicating unit 27 extending on both sides of the pulse generatingdisc 25 preferably comprises a light source and a photo diode, but alsoother embodiments are possible; For each indicating hole 26 passing theindicating unit 27 the indicating unit 27 sends a pulse to thecalculating unit 1, which via memory cells for the various numberpositions sends pulses to the relays 36 of the different numberpositions.

The operation of the device will be explained below with reference toFIGS. 35. When the operator wishes to print a character or numbercombination previously fed into the calculating unit or calculatedtherein,

which number combination has been stored in the calculating unit, heoperates a special key on the control unit, thus causing the calculatingunit 1 to receive an order impulse for effecting setting of the printingunit 4 and printing of the number combination or value desired. All theblocking wheels 13 in the position selection means 3 will at this timebe positioned in the starting position shown in FIG. 3, in which thelong blocking tooth 41 engages the blocking stud 38 so that the settingunit 12 is not in engagement with the setting shaft 11. The upperblocking device 33 is in its intermediate position and is held by meansof the spring 37 with its lower abutment 44 in engagement with thelocking member 45 on the lower blocking device 34 which is in its upperposition unaffected by the relay 36. The cam follower 28 has justengaged the inner cam surface 48 and thus the arm 29 holds the bar 31 insuch a position within the hole 42 that a rotation of the upper blockingdevice 33 corresponding to the displacement of the locking member 45from the lower abutment 44 to the upper abutment 43 is possible. In theposition thus described the indicating wheel 19 as well as thecorresponding type wheel in the printing unit 4 are set in the positionshowing the character 0. The first indicating hole 26 on the pulsegenerating disc 25, corresponding to the character 9, is on its way intothe indicating unit 27.

The cam disc 23, the pulse generating disc 25 and the setting shaft 1 1are all arranged to rotate counterclockwise, in the direction of thearrow 49. Seen in the clockwise direction, the various notches 39 on theblocking wheel starting from the long block tooth 41 correspond each toa number or character from l to 9 and 0".

When the operating key on the control unit 2 is depressed, or when thecalculating unit 3 receives a required signal in any other way, thesetting shaft 11, the cam disc 23 and the pulse generating disc 25 startto rotate simultaneously in the same direction, as indicated by thearrow 49. At the same time as the setting shaft 11 rotates within thestill-standing setting unit 12, one indicating hole 26 after the otherpasses through the indicating unit 27 while the inner cam surface 48 isadvanced under the cam follower 28. Pulses transmitted from theindicating unit 27 to the calculating unit 1 are in the calculating unitcompared to a previously stored value for the number position inquestion. When the number of pulses transmitted from the indicating unitcorresponds to the predetermined number value stored in said numberposition, a pulse is transmitted to the relay 36.

This causes the lower blocking device 34 to be brought to its downmostposition and the spring 37 to pull down the upper blocking device 33 sothat the upper abutment 43 will engage the locking member 45. The resultis that the blocking stud 38 will move away from the long blocking tooth41, thus causing the clutch provided in the setting unit 12 to engagethe setting shaft 11 so that the setting unit rotates together with saidshaft (see FIG. 4). When setting the character 9, the setting shaft 11has rotated only one tenth of a revolution from the starting positionwhen the clutch engages, whereas when setting the character 1" the shafthas rotated nine tenth of a revolution, when the clutch engages.

During continued rotation of the setting shaft 11 the gear wheel 14 now,via the intermediate wheel 17,

turns both the indicating wheel 19 and the setting wheel 20, which viathe shaft 21 operates the printing unit 4. When the cam follower 28slides upon the outer cam surface 46 the upper blocking device 33 is bythe bar 31 moved to its upper position and disengages the setting unit12 from the setting shaft II (see FIG. 5). At the same time the relay 36is deactionated and the spring 37 pulls the lower blocking device 34 toits upper position, shown in FIG. 5. This occurs simultaneoulsy for allof the number positions when the setting shaft 11 has rotated onerevolution from the starting position, i.e., when all the indicatingslots or holes 26 have passed through the indicator 27.

In the position shown in FIG. 5 the character 8 has been set, and duringthe continued rotation of the cam disc 23 other work functions such asprinting occur, while the setting unit is standing still. The varioussetting movements are thus initiated at different points in timedetermined by the values in the respective number positions. However,all the movements are terminated at the same time. Resetting of all ofthe setting units I2 is initiated when the intermediate cam surface 47slides in beneath the cam follower 28. The bar 31 is moved so fardownward that the spring 37 can pull down the upper blocking device 33to its intermediate position where the short blocking teeth 40 can passthe blocking stud 38 (see FIG. 3). When this has happened the settingunit 12 engages with the setting shaft II and rotates with the sameuntil the long blocking tooth hits against the blocking stud 38, anddisengagement occurs so that the starting position shown in FIG. 3 isreturned to. In this way a reliable resetting at all the numberpositions is achieved. In contrast to what is usually the case acontinuous rotational movement of the setting shaft 11 is utilized toperform the setting as well as the resetting. Thus all problems withreciprocating guide rules and similar mechanisms are completelyeliminated.

The device shown in FIGS. 3-5 can of course be constructed in a numberof differnet ways, while essentially retaining the function. FIGS. 6-8show a preferred embodiment in which the upper blocking device 33 has adifferent construction and in which the disc 22 is a combined cam discand pulse generating disc. The end of the upper blocking device 33 whichis farthest from the blocking stud 38 is constructed as a cam follower50 which can contact either the outer cam surface 51 or the inner camsurface 52 or be at an intermediate position between them. In thestarting position shown in FIG. 6 the upper blocking device 33 is in itsintermediate position in which the blocking stud 38 bears on the longblocking tooth 41 so that the setting unit I2 is disengaged. The camfollower 50 is in an intermediate position a bit above the inner camsurface 52. In the position shown in FIG. 7 the relay 36 has just beenactivated and has pulled down the lower blocking device 34 havingthereby brought the setting unit I2 into engagement with the settingshaft II. The cam follower 50 now slides along the inner cam surface 52.

In the position shown in FIG. 8 the cam follower 50 has slid up on theouter cam surface 51, thereby forcing the upper blocking device into itsupper position for disengaging the setting unit 12, which has nowreached the desired position. The electrical current to the relay 36 isbroken and the spring 37 has returned the lower blocking device 34 toits upper position. Resetting is initiated when the cam follower 50slides down from the outer cam surface 5 I and thereby brings thesetting unit I2 into engagement with the setting shaft II for such alarge part of its revolution that the long blocking tooth again reachesthe starting position shown in FIG. 6 in which the setting unit isdisengaged.

As will be understood from both of the described examples above, thesetting of the character 0 is obtained by the blocking wheel 13remaining in its starting position since the pulse generating disc nevergives off a zero impulse and, accordingly, the relay 36 will not becomeactivated. The gear ratio between the setting shaft II on the one handand the cam disc and the pulse generating disc on the other hand can beselected in various ways, and it is also not necessary that the cam discand the pulse generating disc have the same shaft. Other positioningsand constructions than those given here can also be used.

One of the prerequisites for the proper functioning of the devicedescribed is that the setting unit I2 can be quickly and effectivelybrought into engagement with the setting shaft II, and after thecompleted movement be quickly and effectively disengaged again.

A suitable embodiment of the setting unit I2 is shown in FIGS. 9 andIII. As will be seen from FIG. It), a sleeve 53 has been mounted ontothe setting shaft II, since sleeve having a shoulder 5 The sleeve 53 isrotationally fixed relative to the setting shaft II by means of a pin 55extending through the shoulder 54 and the setting shaft II. A ring 56 ismounted onto the shoulder 54 and is rotatable on the same and is furthersecured to the blocking wheel I4. Both rings 56 and 57 and the sleeve 53have the same outer diameter, and it is important that the deviationbetween the diameters is kept within rather narrow limits. The mantlesurface formed by the ring 57, the sleeve 53 and the rings 56 isenclosed by a helical spring 58 which by means of fastening members 59and 60 is secured at its ends on the respective ring 56 and 57. Thehelical spring 58 is closely winded so that a plurality of spring turnswill enclose the sleeve 53. In the gear wheel I4 is secured a pin IIIwhich with its free end extends through a hole 62 provided in theblocking wheel I3. The diameter of the hole 62 is greater than thediameter of the free end of the pin M. The direction of winding thethread of the helical spring 58 is selected such that the spring, whenthe gear wheel 14- is arrested, and the blocking wheel I3, seen in thedirection towards the gear wheel I I, is turned clockwise, tends toincrease its diameter.

When the blocking wheel I3 is not actuated by any force, that is whenthe blocking stud 33 is not in engagement with any of the blocking teeth44) or 41, the helical spring will grip the sleeve 53 with such a forcethat the whole setting unit I2 is brought to rotate together with thesleeve 53 and the setting shaft II. In order to disengage the settingunit I2, the diameter of the helical spring 53 must be increased so muchthat the spring will release its grip around the sleeve 53. This iseffected by moving the blocking stud 38 into engagement with therotating blocking wheel I4 so that it will rest against any of theblocking teeth and prevent further rotation of the blocking wheel. Theforce required for disengagement is very small, and the friction and/orinertia of those gear wheels which are directly or indirectly actuatedby the gear wheel I4 is often sufficiently great to produce a forcewhich will retain the gear wheel I I in the desired position. However,if the gear wheel I4 due to play can be rotated to such an angle thatdisengagement will occur, the setting unit 12 will be rotated so muchthat the blocking tooth will again be pressed against the blocking stud38 and thus after sufficiently small turning again will disengage thesetting unit. The sleeve 53 will accordingly in such case in someinstances slip within the helical spring 58, but all the time theposition of the setting unit will be main tained so that the blockingstud 38 will prevent rotation. The pin 61 and the hole 62 will serve asa locking mechanism in order to lock the blocking wheel 13 and the gearwheel 14 to each other upon a certain permitted rotational movement.

The embodiment of the setting unit described may be varied in severalways. For example, the helical spring 58 may be used without any sleeve53 and may grip directly around the setting shaft 11. It may with itsend portions be directly secured to the blocking wheel 13 or the gearwheel 14, respectively. It will also be possible to eliminate the camdisc and the cam follower mechanism and insteadprovide a modified pulsegenerating disc controlling a blocking which comprises one or morerelays or similar members. Also, the power source may, with a suitablepower transmission system, be used for driving for instance a printingunit or for effecting other functions. The pulse transmitter may forexample be so constructed that the pulse generating disc has a shapesimilar to a gear wheel, or one can also for instance use a device whichgenerates a varying magnetic field.

In order to safely attain that the setting unit be rotated exactly thepredetermined portion of a revolution, it is important that the timebetween the disengagement of the blocking mechanism and the engagementof the blocking wheel is well adapted to the speed of rotation of thesetting shaft. if the blocking mechanism should be disengaged too early,the setting unit will rotate too far, and if the disengagement is madetoo late, the setting unit will not be able to rotate sufficiently far.The synchronizing of the pulse transmitter is therefore important.

The advantage of the coupling of the type described is that it willresult in a high power transmission capacity in relation to the controlforce required for effecting engagement or disengagement, and further itis quick to operate because the actuating movement may be made quitesmall. The wear caused by a rotating setting shaft, with or without asleeve, will be small. In relation to prior devices the device accordingto the invention will be much simpler, more reliable and less expensiveto manufacture and may further be constructed to form a compact device.

The type of coupling described may also be used for other applications,for instance when it is desired to obtain an intermittent rotation withpredetermined intervals of rotation. The blocking mechanism and theblocking wheel may then be given such a shape that the blockingmechanism will let the blocking wheel free at predetermined intervals.

What is claimed is:

l. A position selecting device for transferring number of charactervalues having at least one position and represented by electrical pulsesin an electronic calculating unit to mechanical indicating means such asa mechanical calculating or printing unit or the like, and for settingthe values so represented, said selecting device comprising a. a powersource,

b. a setting shaft rotatable in only one direction, said setting shaftbeing driven by said power source,

c. a plurality of rotatable setting units, one for each number position,each setting unit having a first position thereof which is the normaland reset position thereof, and a second position thereof which is thesetting position thereof, each setting unit upon rotation thereof foroperating said mechanical indicating means, each setting unit beingrotatable in only one direction from said first position thereof,through said second position thereof, and back to said first positionthereof,

d. means for providing selective engagement and disengagement betweensaid setting shaft and each of said setting units to provide either forrotation of each of said setting units with said setting shaft or norotation of each of said setting units with said setting shaft, saidsetting shaft being common to all setting units,

e. a pulse transmitter common to all number positions, said pulsetransmitter operatively connected to said power source to rotatesynchronously with said setting shaft and adapted to determine saidsecond positions of said setting units, and

f. means for providing simultaneous disengagement of all said settingunits from said setting shaft, said means comprising (i) a blockingmechanism for each setting unit, each blocking mechanism having a firstposition thereof during which its corresponding setting unit is inengagement with said setting shaft for rotation therewith toward saidsecond position thereof, a second position thereof corresponding to itscorresponding setting unit being in its second position thereof, and athird position thereof corresponding to its corresponding setting unitbeing in its first position thereof or rotating toward said firstposition thereof, and (ii) a cam disc common to all said setting unitsand corresponding blocking members, said cam disc operatively connectedto said power source to simultaneously rotate with said setting shaft,said cam disc for operating said blocking mechanisms simultaneously fromsaid first to said second position thereof and from said second positionto said third position thereof while not interfering with movement ofsaid blocking member from said third to said first position thereof.

2. A device as recited in claim 1 further comprising a relay operativelyassociated with each of said setting units for moving its correspondingblocking member from its third to its second position thereof, saidrelay being controlled by said pulse transmitter.

3. A device as recited in claim 2 wherein each of said blockingmechanisms comprises a first blocking device adapted to cooperate withits corresponding setting unit and adapted to be actuated by said camdisc, and a second blocking device operatively connected with said relayand adapted to actuate said first blocking device.

4. A device as recited in claim 1 wherein said pulse transmittercomprises a pulse generating disc which is synchronously movable withsaid setting shaft and is provided with indicating holes therein, and apulse transmitting sensor cooperating with said pulse generating disc.

5. A device as recited in claim 4 wherein said cam disc and said pulsedisc are integral.

6. A device as recited in claim wherein said means for providingselective engagement between said setting shaft and each of said settingunits comprises a helical spring enclosing said setting shaft andforming a coupling between said setting shaft and said setting unit,said helical spring adapted to transmit the rotational movement of thesetting shaft, by friction between the windings of the spring and thesetting shaft or a thickened portion thereof, to said indicating means.

7. A device as recited in claim 6 wherein said spring is closely woundand has an inner diameter of such dimensions relative to the outerdiameter of said setting shaft or said thickened portion thereof, that asmall disengaging movement of the end portions of said spring increasesthe outer diameter thereof sufficiently to disengage the setting unitfrom said setting shaft.

8. A device as recited in claim 7 wherein one end portion of saidhelical spring is secured to a blocking wheel cooperating with saidblocking mechanism, the other end portion of said helical spring beingsecured to a gear wheel cooperating with said indicating means.

9. A device as recited in claim 8 wherein the periphery of said blockingwheel is provided with a number of blocking teeth corresponding to thedesired number p of setting positions, one of said blocking teeth beinglonger than the others.

10. A device as recited in claim 8 wherein each end portion of saidhelical spring is secured to a rotatable ring located on either side ofand concentric with said setting shaft, said rings being secured to saidblocking wheel and said gear wheel respectively, each spring end beingsecured to its corresponding ring by a fastening member enclosing saidend portion of said spring.

ill. A device as recited in claim 10 wherein a locking mechanism isdisposed between the end portions of said spring for limiting thetorsion of said spring ends relative to one another.

12. A device as recited in claim 6 wherein a locking mechanism isdisposed between the end portions of said spring for limiting thetorsion of said spring ends relative to one another.

1. A position selecting device for transferring number of charactervalues having at least one position and represented by electrical pulsesin an electronic calculating unit to mechanical indicating means such asa mechanical calculating or printing unit or the like, and for settingthe values so represented, said selecting device comprising a. a powersource, b. a setting shaft rotatable in only one direction, said settingshaft being driven by said power source, c. a plurality of rotatablesetting units, one for each number position, each setting unit having afirst position thereof which is the normal and reset position thereof,and a second position thereof which is the setting position thereof,each setting unit upon rotation thereof for operating said mechanicalindicating means, each setting unit being rotatable in only onedirection from said first position thereof, through said second positionthereof, and back to said first position thereof, d. means for providingselective engagement and disengagement between said setting shaft andeach of said setting units to provide either for rotation of each ofsaid setting units with said setting shaft or no rotation of each ofsaid setting units with said setting shaft, said setting shaft beingcommon to all setting units, e. a pulse transmitter common to all numberpositions, said pulse transmitter operatively connected to said powersource to rotate synchronously with said setting shaft and adapted todetermine said second positions of said setting units, and f. means forproviding simultaneous disengagement of all said setting units from saidsetting shaft, said means comprising (i) a blocking mechanism for eachsetting unit, each blocking mechanism having a first position thereofduring which its corresponding setting unit is in engagement with saidsetting shaft for rotation therewith toward said second positionthereof, a second position thereof corresponding to its correspondingsetting unit being in its second position thereof, and a third positionthereof corresponding to its corresponding setting unit being in itsfirst position thereof or rotating toward said first position thereof,and (ii) a cam disc common to all said setting units and correspondingblocking members, said cam disc operatively connected to said powersource to simultaneously rotate with said setting shaft, said cam discfor operating said blocking mechanisms simultaneously from said first tosaid second position thereof and from said second position to said thirdposition thereof while not interfering with movement oF said blockingmember from said third to said first position thereof.
 2. A device asrecited in claim 1 further comprising a relay operatively associatedwith each of said setting units for moving its corresponding blockingmember from its third to its second position thereof, said relay beingcontrolled by said pulse transmitter.
 3. A device as recited in claim 2wherein each of said blocking mechanisms comprises a first blockingdevice adapted to cooperate with its corresponding setting unit andadapted to be actuated by said cam disc, and a second blocking deviceoperatively connected with said relay and adapted to actuate said firstblocking device.
 4. A device as recited in claim 1 wherein said pulsetransmitter comprises a pulse generating disc which is synchronouslymovable with said setting shaft and is provided with indicating holestherein, and a pulse transmitting sensor cooperating with said pulsegenerating disc.
 5. A device as recited in claim 4 wherein said cam discand said pulse disc are integral.
 6. A device as recited in claim 5wherein said means for providing selective engagement between saidsetting shaft and each of said setting units comprises a helical springenclosing said setting shaft and forming a coupling between said settingshaft and said setting unit, said helical spring adapted to transmit therotational movement of the setting shaft, by friction between thewindings of the spring and the setting shaft or a thickened portionthereof, to said indicating means.
 7. A device as recited in claim 6wherein said spring is closely wound and has an inner diameter of suchdimensions relative to the outer diameter of said setting shaft or saidthickened portion thereof, that a small disengaging movement of the endportions of said spring increases the outer diameter thereofsufficiently to disengage the setting unit from said setting shaft.
 8. Adevice as recited in claim 7 wherein one end portion of said helicalspring is secured to a blocking wheel cooperating with said blockingmechanism, the other end portion of said helical spring being secured toa gear wheel cooperating with said indicating means.
 9. A device asrecited in claim 8 wherein the periphery of said blocking wheel isprovided with a number of blocking teeth corresponding to the desirednumber of setting positions, one of said blocking teeth being longerthan the others.
 10. A device as recited in claim 8 wherein each endportion of said helical spring is secured to a rotatable ring located oneither side of and concentric with said setting shaft, said rings beingsecured to said blocking wheel and said gear wheel respectively, eachspring end being secured to its corresponding ring by a fastening memberenclosing said end portion of said spring.
 11. A device as recited inclaim 10 wherein a locking mechanism is disposed between the endportions of said spring for limiting the torsion of said spring endsrelative to one another.
 12. A device as recited in claim 6 wherein alocking mechanism is disposed between the end portions of said springfor limiting the torsion of said spring ends relative to one another.